Seems like a generalization but Canadians will complain about every little inconvenience. Brits do it best IMHO. But in reality it comes with living in a country where most things are going well for us, but small inconveniences are worthy of a complaint. Or worthy of/or requiring calls for the government to step in somehow to rescue.
People still have expectations when it comes to air travel, with the cost of travel being high and people wanting to get their money's worth. Most of us on this forum hopefully know that the cost of the ticket most of the time only pertains to that, getting us from point A to point B.
It doesn't help that the industry thrives on segmentation, where the guy next to you could be getting all the frills and you are not: the difference being that he paid more but you have no way of telling that since all you see is that he's sharing an armrest with you.
There was also an article I read a few weeks ago (I can't find the link) that talks about how airlines are degrading Economy service to the point where the passenger will want to spend more to have an experience that's better but used to be the norm.